Semiconductor Device, Liquid Crystal Display Panel, and Mobile Information Terminal

ABSTRACT

A semiconductor device includes a plurality of sets of external drive terminals in a marginal region along one long side of a rectangular semiconductor substrate, a plurality of sets of ESD protection circuits arranged in the marginal region and coupled to corresponding sets of the drive terminals, and a plurality of output circuits coupled to corresponding sets of the drive terminals. Each set of drive terminals in a plurality of n columns along a Y direction is laid out in a staggered arrangement with drive terminals in adjacent columns shifted relative to each other. Each output circuit includes n output units associated with n drive terminals of each set and arranged in one column in an X direction. By the arrangement, the drive terminals can be arranged at a narrower pitch, and the total width for n output units can be compacted into that of one output circuit.

CROSS-REFERENCE TO RELATED APPLICATIONS

The disclosure of Japanese Patent Application No. 2010-260753 filed onNov. 24, 2010 including the specification, drawings and abstract isincorporated herein by reference in its entirety.

BACKGROUND

The present invention relates to a semiconductor device having a largenumber of juxtaposed external drive terminals and, moreover, a liquidcrystal display panel and a mobile information terminal equipped withsuch semiconductor device as a display driver, and also relates to atechnique that is effectively applied to, for example, a mobile phoneequipped with a small and high-definition liquid crystal display.

In an active matrix type liquid crystal display, the switching gates ofa large number of thin-film transistors arranged in a matrix are turnedon sequentially per scan line in accordance with horizontalsynchronization timing, a driving voltage is supplied from source linesto the turned on thin-film transistors and thus applied to sub-pixels.This active matrix type liquid crystal display is widely used in avariety of mobile information terminals or the like typified by mobilephones and, as its display definition is enhanced to a higherdefinition, the number of external drive terminals increases. If thenumber of these external drive terminals increases, the external driveterminals of a liquid crystal display driver that drives the liquidcrystal display have to be laid out at a narrower pitch. For example,when a liquid crystal display driver formed over a rectangularsemiconductor substrate is placed along an edge of a liquid crystaldisplay, as the number of source electrode lines which are led out fromthe edge of the liquid crystal display increases due to enhanceddefinition of the display, it becomes necessary to increase the numberof external drive terminals to be formed in line with a long side of theliquid crystal display driver because of size limitation of the liquidcrystal display driver.

Patent Document 1 describes laying out a plurality of arrays of both I/Opads as external terminals and I/O circuits coupled to the I/O pads inedge regions of a chip and enabling an increase in the number of I/Opads and I/O circuits of a semiconductor integrated circuit. It alsomentions that the I/O pads are laid out in a staggered arrangement.

Patent Document 2 describes laying out input/output circuits whichincrease with increasing external terminals in a staggered arrangement,so that this arrangement can provide sufficient space for laying out theinput/output circuits.

RELATED ART DOCUMENTS Patent Documents

-   [Patent Document 1] Japanese Unexamined Patent Publication No.    2005-252095-   [Patent Document 2] Japanese Unexamined Patent Publication No. Hei    4(1992)-127556

SUMMARY

However, the techniques of the foregoing Patent Documents are incapableof sufficiently meeting a requirement that external terminals should bearranged at a narrower pitch due to an increase in the number ofexternal terminals. As described in Patent Document 1, the arrangementin which each set of I/O pads in a plurality of columns or rows is laidout in a staggered arrangement is applicable only if the width of an I/Ocircuit is smaller than a minimum pitch for the I/O pads. As describedin Patent Document 2, the arrangement in which each set of I/O circuitsin a plurality of columns or rows is laid out in a staggered arrangementis applicable if the width of an I/O circuit is larger than a minimumpitch for I/O pads, but the pitch for the I/O pads is restricted to adimension that is 1.5 times as much as the width dimension of an I/Ocircuit.

An object of the present invention is to provide a semiconductor devicethat sufficiently complies with a requirement that external driveterminals should be arranged at a narrower pitch.

Another object of the present invention is to provide a liquid crystaldisplay panel and, moreover, a mobile information terminal featuring anarrower pitch array of external drive terminals of a semiconductordevice for driving pixels of a display to enable size reduction in orderto meet size reduction and enhanced definition of the display.

The above-noted and other objects and novel features of the presentinvention will become apparent from the description of the presentspecification and the accompanying drawings.

A typical aspect of the invention disclosed in this application isoutlined as follows.

There is provided a semiconductor device including a plurality of setsof external drive terminals arranged in a marginal region along one longside of a rectangular semiconductor substrate; a plurality of sets ofESD protection circuits also arranged in the marginal region and coupledto the corresponding sets of the external drive terminals; and aplurality of output circuits coupled to the corresponding sets of theexternal drive terminals. The sets of the external drive terminals arearranged such that each set of the external drive terminals in aplurality of n columns along a Y direction is laid out in a staggeredarrangement in which the positions of the external drive terminals inadjacent columns are shifted with respect to each other. Each of theoutput circuits includes n output units associated with n external driveterminals of each set and arranged in one column in an X directionperpendicular to the Y direction.

Accordingly, by the staggered arrangement in n columns, the externaldrive terminals can be arranged at a narrower pitch. In each outputcircuit which is associated with each set of n external drive terminals,by locating n output units arranged in one column in the X direction,the total width for n output units can be compacted into the width ofone output circuit. It is thus possible to reduce the layout width of anoutput circuit constrained by laying out the external drive terminals ata narrower pitch.

Effect obtained by the typical aspect of the invention disclosed in thepresent application is outlined below.

It is possible to sufficiently comply with the requirement that theexternal drive terminals of the semiconductor device should be arrangedat a narrower pitch. An inventive feature in terms of narrower pitchlayout of the external drive terminals of the semiconductor device fordriving pixels of the display can contribute to the realization of asmaller liquid crystal display panel and, moreover, a smaller mobileinformation terminal in order to meet size reduction and enhanceddefinition of the display.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a layout diagram illustrating details on relative layouts ofexternal drive terminals, ESD protection circuits, and output circuitsin a liquid crystal display driver as one embodiment of the presentinvention.

FIG. 2 is a layout diagram schematically depicting a chip layoutstructure of the liquid crystal display driver as one embodiment of thepresent invention.

FIG. 3 is a layout diagram representatively illustrating a positionalrelationship in which a set of ESD protection circuits and an outputcircuit which are associated with each other are relatively far fromeach other in the Y direction.

FIG. 4 is a circuit diagram illustrating a circuit configuration ofoutput units of an output circuit.

FIG. 5 is a layout diagram illustrating details on relative layouts ofexternal drive terminals, ESD protection circuits, and output circuits,when each set of external drive terminals in two columns is laid out ina staggered arrangement as a second embodiment of the present invention.

FIG. 6 is a schematic diagram illustrating a mobile phone as an exampleof a mobile information terminal as a third embodiment of the presentinvention.

FIG. 7 is a plan view outlining a configuration as a comparison examplein which one set of a select switch, an output amplifier, a tone levelselecting circuit, and a latch circuit is associated with one externaldrive terminal and arranged in one column, even if external driveterminals are laid out in a staggered arrangement.

DETAILED DESCRIPTION 1. General Description of Embodiments

To begin with, exemplary embodiments of the invention disclosed hereinare outlined. In the following general description of exemplaryembodiments, reference designators in the drawings, which are given forreferential purposes in parentheses, are only illustrative of elementsthat fall in the concepts of the components identified by thedesignators.

[1] <Staggered arrangement of each set of external drive terminals in aplurality of columns and arrangement of output units in a plurality ofcolumns> A semiconductor device (1) pertaining to an exemplaryembodiment of the present invention includes a plurality of sets ofexternal drive terminals (3A to 3C, 3 mA to 3 mB) arranged in a marginalregion along one long side of a rectangular semiconductor substrate; aplurality of sets of ESD protection circuits (4A to 4C, 4 mA to 4 mB)also arranged in the marginal region and coupled to the correspondingsets of the external drive terminals; a plurality of output circuits (5,5 m) coupled to the corresponding sets of the external drive terminals;and a processing circuit (6) formed over the semiconductor substrate tocontrol output operation of the output circuits. The sets of theexternal drive terminals are arranged such that each set of the externaldrive terminals in a plurality of n columns along a Y direction is laidout in a staggered arrangement in which the positions of the externaldrive terminals in adjacent columns are shifted with respect to eachother. Each of the output circuits includes n output units (5A to 5C, 5mA to 5 mB) associated with n external drive terminals of each set andarranged in one column in an X direction perpendicular to the Ydirection.

Accordingly, by the staggered arrangement in n columns, the externaldrive terminals can be arranged at a narrower pitch. In each outputcircuit which is associated with each set of n external drive terminals,by locating n output units arranged in one column in the X direction,the total width for n output units can be compacted into the width ofone output circuit. It is thus possible to reduce the layout width of anoutput circuit constrained by laying out the external drive terminals ata narrower pitch.

[2] <Output units in even width> In the semiconductor device as setforth in [1], n output units arranged in one column in the X directionare arranged in order in an even width in the X direction.

Forming n output units in a region with a predetermined width isfacilitated.

[3] <Layered configuration> In the semiconductor device as set forth in[2], a region where the ESD protection circuits and the output circuitsare formed is located underneath a region where the external drivecircuits are arranged in a layered configuration.

It is possible to improve the efficiency of laying out circuit elementsover a semiconductor substrate.

[4] <Making the output circuit width smaller than the layout width foreach set of external drive terminals> In the semiconductor device as setforth in [1], a width dimension (5W, 5 mW) in the Y direction of each ofthe output circuits is smaller than a width dimension (4W, 4 mW) of eachset of n external drive terminals arranged along the X direction.

It will be easy to reserve a surplus region for locating another circuitin a space provided between the arrays of output circuits laid out inthe Y direction.

[5] <Column-wise alignment of the ESD protection circuits arranged withthe external drive terminals arranged> In the semiconductor device asset forth in [4], the ESD protection circuits of each set are juxtaposedin the Y direction at a pitch that is equal to a layout pitch in the Ydirection for the external drive terminals of each set laid out in the ncolumns along the Y direction.

Since the ESD protection circuits can be arranged near the externaldrive terminals, it is possible to make assurance doubly sure onprotection against ESD (Electrostatic Discharge).

[6] <Wiring region> The semiconductor device as set forth in [5] furtherincludes a wiring region (9) for coupling corresponding ones of theexternal drive terminals and output units between an array region of theESD protection circuits along the Y direction and an array region of theoutput units along the Y direction.

When the ESD protection circuits have been arranged near the externaldrive terminals, it will be easy to route wiring lines for coupling theoutput circuits to the corresponding external drive terminals.

[7] <Extending a region for forming an internal circuit> Thesemiconductor device as set forth in [4] has array regions of the outputcircuits extending from a center part of the semiconductor substratetoward right and left sides of the substrate along the Y direction and apart of the processing circuit is formed in a space (6A) between theright and left array regions of the output circuits.

A surplus region between the right and left array regions of the outputcircuits in the Y direction can be used effectively for locating theprocessing circuit and it is possible to improve the layout efficiencyfor locating circuits all over the semiconductor substrate.

[8] <Host interface> The semiconductor device as set forth in [1]further includes a plurality of external interface terminals (7)arranged in a marginal region along the other long side of thesemiconductor substrate and the external interface terminals are coupledto the processing circuit.

Host interface with the processing circuit, among others, can beimplemented via the external interface terminals.

[9] <Pitch for the external interface terminals and pitch for theexternal drive terminals> In the semiconductor device as set forth in[8], a layout pitch for the external drive terminals is smaller than alayout pitch for the external interface terminals.

As for external terminals not required to be laid out at a narrowerpitch, there is no need for the above-described considerations withregard to the external drive terminals.

[10] <Output units that drive source electrodes of liquid crystaldisplay> In the semiconductor device as set forth in [9], the externaldrive terminals are terminals for driving source electrodes of an activematrix type liquid crystal display (111). Each of the output unitsincludes a latch circuit (50A to 50C, 50 mA to 50 mB) that latchesdisplay data supplied from the processing circuit, atone level selectingcircuit (51A to 51C, 51 mA to 51 mB) that decodes display data latchedby the latch circuit and selects a tone level voltage signal, an outputamplifier (52A to 52C, 52 mA to 52 mB) that amplifies a tone levelvoltage signal output from the tone level selecting circuit, and aselect switch (53A to 53C, 53 mA to 53 mB) that selects either an outputwith a polarity from the output amplifier or an output with an oppositepolarity from another output unit's output amplifier and outputs theselected output to a corresponding one of the external drive terminals.

It is possible to allow for narrower pitch layout of the external driveterminals of the semiconductor device for use to drive a smaller andhigher-definition liquid crystal display.

[11] <Liquid crystal display panel> A liquid crystal display panel (104)pertaining to another embodiment of the present invention includes anactive matrix type liquid crystal display (111) formed over a glasssubstrate (110); a plurality of source electrode lines (112) led outfrom the active matrix type liquid crystal display and formed over theglass substrate; and a liquid crystal display driver (1), as asemiconductor integrated circuit, coupled to the source electrode linesand mounted over the glass substrate. The liquid crystal display driverincludes a plurality of sets of external drive terminals arranged in amarginal region along one long side of a rectangular semiconductorsubstrate, the one long side facing an edge of the active matrix typeliquid crystal display; a plurality of sets of ESD protection circuitsalso arranged in the marginal region and coupled to the correspondingsets of the external drive terminals; a plurality of output circuitscoupled to the corresponding sets of the external drive terminals; and aprocessing circuit formed over the semiconductor substrate to controloutput operation of the output circuits. The sets of the external driveterminals are arranged such that each set of the external driveterminals in a plurality of n columns along a Y direction is laid out ina staggered arrangement in which the positions of the external driveterminals in adjacent columns are shifted with respect to each other.Each of the output circuits includes n output units associated with nexternal drive terminals of each set and arranged in one column in an Xdirection perpendicular to the Y direction.

Because, as is evident from the foregoing description, it is possible tosufficiently comply with the requirement that the external driveterminals of the liquid crystal display driver should be arranged at anarrower pitch, the inventive feature in terms of narrower pitch layoutof the external drive terminals of the semiconductor device for drivingpixels of the display can contribute to the realization of a smallerliquid crystal display panel in order to meet size reduction andenhanced definition of the liquid crystal display.

[12] <Mobile information terminal> A mobile information terminal (100)pertaining to another embodiment of the present invention includes aninput unit (102); a data processing unit (103) that performs dataprocessing according to an input signal from the input unit; and adisplay unit (104) for display under control of the data processing unitin the mobile information terminal's casing (101). The display unitincludes a display (111); electrode lines (112) led out from thedisplay; and a display driver (1) coupled to the electrode lines on itsone side and coupled to the data processing unit on its other side. Thedisplay driver includes a plurality of sets of external drive terminalsarranged in a marginal region along one long side of a rectangularsemiconductor substrate, the one long side facing an edge of thedisplay; a plurality of sets of ESD protection circuits also arranged inthe marginal region and coupled to the corresponding sets of theexternal drive terminals; a plurality of output circuits coupled to thecorresponding sets of the external drive terminals; and a processingcircuit formed over the semiconductor substrate to control outputoperation of the output circuits. The sets of the external driveterminals are arranged such that each set of the external driveterminals in a plurality of n columns along a Y direction is laid out ina staggered arrangement in which the positions of the external driveterminals in adjacent columns are shifted with respect to each other.Each of the output circuits includes n output units associated with nexternal drive terminals of each set and arranged in one column in an Xdirection perpendicular to the Y direction.

Because, as is evident from the foregoing description, it is possible tosufficiently comply with the requirement that the external driveterminals of the liquid crystal display driver should be arranged at anarrower pitch, the inventive feature in terms of narrower pitch layoutof the external drive terminals of the semiconductor device for drivingpixels of the display can contribute to the realization of a smallermobile information terminal in order to meet size reduction and enhanceddefinition of the liquid crystal display.

[13] <Mobile phone> The mobile information terminal as set forth in [12]further includes a communication processing unit that implements mobilecommunication control based on control of the data processing unit.

The mobile information terminal can be implemented as a mobile phone.

2. Details on Embodiments

Embodiments of the invention will now be described in greater detail.

First Embodiment

FIG. 2 schematically depicts a chip layout structure of a liquid crystaldisplay driver as one embodiment of the present invention. The liquidcrystal display driver 1 shown in FIG. 2 is, for example, formed over asingle semiconductor substrate 2 such as a monocrystalline siliconsubstrate by a CMOS integrated circuit or Bi-CMOS integrated circuitmanufacturing technology known to the public.

The semiconductor substrate 2 has a rectangular shape and, in a marginalregion of one long side 2A thereof, a plurality of sets of externaldrive terminals 3A, 3B, 3C are arranged such that, each set of theexternal drive terminals in a plurality of columns, for example, threecolumns along a Y direction parallel to the long side is laid out in astaggered arrangement in which the positions of the external driveterminals 3A, 3B, 3C in adjacent columns are shifted with respect toeach other. These sets of the external drive terminals 3A, 3B, 3C, forexample, serve as terminals that drive source lines of an active matrixtype liquid crystal display. In edge sections of the marginal region ofthe long side 2A of the semiconductor substrate 2 in the Y direction,terminals that drive gate lines of the liquid crystal display, ESDprotection circuits, and output circuits are arranged, though they arenot shown here. The external drive terminals 3A, 3B, 3C are formed, forexample, by solder bump electrodes.

In the vicinity of the array of the thus arranged external driveterminals 3A, 3B, 3C, a plurality of sets of ESD protection circuits 4A,4B, 4C coupled to the corresponding sets of the external drive terminals3A, 3B, 3C and a plurality of output circuits 5 coupled to thecorresponding sets of the external drive terminals 3A, 3B, 3C arearranged along the same Y direction. To simplify diagrammaticrepresentation, in FIG. 2, one rectangle representing ESD protectioncircuits 4A, 4B, 4C represents a collection of three ESD protectioncircuits 4A, 4B, 4C for convenience sake. Each output circuit 5 includesthree output units respectively associated with three external driveterminals 3A, 3B, 3C. Details on the output units will be describedlater based on FIG. 1.

A layout pitch for the output circuits 5 is smaller than layout pitchesfor the ESD protection circuits 4A, 4B, 4C and the external driveterminals 3A, 3B, 3C. Accordingly, the output circuits 5 are arranged inright and left side arrays between which a central empty space isprovided. This empty space region is incorporated in a part 6A of acircuit area of a processing circuit 6 that is formed in the center partof the semiconductor substrate 2. Although not restrictive, theprocessing circuit 6, in accordance with commands, stores display datawhich is supplied from outside into a fame buffer, outputs and providesthe display data from the frame buffer to the output circuits 5, andcauses the output circuits 5 to output source line drive signals fromthe external drive terminals 3A, 3B, 3C in sync with horizontal scantiming, and, moreover, controls switching and driving of gate lineswhich are sequentially selected in sync with horizontal scan timing.

Due to the fact that the layout pitch for the output circuits 5 issmaller than the layout pitches for the ESD protection circuits 4A, 4B,4C and the external drive terminals 3A, 3B, 3C, it is needed to routewiring 8 for coupling the output circuits 5 to the ESD protectioncircuits 4A, 4B, 4C of the corresponding external drive terminals 3A,3B, 3C in the Y direction as well as the X direction. Taking this intoconsideration, a wiring region 9 for such wiring is provided between theESD protection circuits 4A, 4B, 4C and the output circuits 5. Details onthis point will be described later.

A region where the ESD protection circuits 4A, 4B, 4C and the outputcircuits 5 are formed is located underneath a region where the externaldrive terminals 3A, 3B, 3C are arranged in a layered configuration withan intervening surface protection film or insulation film.

In a marginal region of the other long side 2B of the semiconductorsubstrate 2, external interface terminals 7 are arranged for interfacingwith a data processing device such as a microcomputer. The dataprocessing device performs data processing and the like for supplyingdisplay data to the liquid crystal display driver 1. Although not shownhere, ESD protection circuits and input/output circuits corresponding tothe external interface terminals 7 are arranged and the input/outputcircuits not shown here are coupled to the processing circuit 6.Although not restrictive, a layout pitch for the external interfaceterminals 7 is larger than the layout pitch for the external driveterminals 3A, 3B, 3C, considering that the requirement that terminalsshould be arranged at a narrower pitch is not so strict for the externalinterface terminals 7 that are coupled to a data processing device, ascompared with the external drive terminals 3A, 3B, 3C.

FIG. 1 illustrates details on relative layouts of external driveterminals 3A, 3B, 3C, ESD protection circuits 4A, 4B, 4C, and outputcircuits 5. In FIG. 1, nine external drive terminals 3A, 3B, 3C, nineESD protection circuits 4A, 4B, 4, and three output circuits 5 are shownby way of example.

One output circuit 5 has three output units 5A, 5B, 5C. Here, theexternal drive terminals 3A, 3B, 3C are terminals for driving sourceelectrodes of the active matrix type liquid crystal display. The outputunits 5A, 5B, 5C, respectively, include latch circuits 50A, 50B, 50Cthat latch display data supplied from the processing circuit 6, tonelevel selecting circuits 51A, 51B, 51C that decode the display datalatched by the latch circuits 50A, 50B, 50C and select a tone levelvoltage signal, output amplifiers 52A, 52B, 52C that amplify tone levelvoltage signals which have been output from the tone level selectingcircuits 51A, 51B, 51C, and select switches 53A, 53B, 53C that selectone of the outputs with opposite polarities from two output amplifiersand output it to the corresponding external drive terminals 3A, 3B, 3C.The output unit 5A includes a latch circuit 50A, a tone level selectingcircuit 51A, an output amplifier 52A, and a select switch 53A. Theoutput unit 5B includes a latch circuit 50B, a tone level selectingcircuit 51B, an output amplifier 52B, and a select switch 53B. Theoutput unit 5C includes a latch circuit 50C, a tone level selectingcircuit 51C, an output amplifier 52C, and a select switch 53C. Here, theoutput units 5A, 5B, 5C are not arranged on a per-unit basis; instead,component circuits of each output unit are arranged together on aper-function basis. For example, the select switches 53A to 53C arearranged in line in the Y direction, whereas the output amplifiers 52A,52B, 52C, the tone level selecting circuits 51A, 51B, 51C, and the latchcircuits 50A, 50B, 50C are arranged in line in the X direction in thementioned order.

A large number of output circuits 5, each occupying one circuit cell,are laid out. One output circuit occupies a rectangular circuit cellhaving a width of 5W.

Also, a large number of ESD protection circuits 4A, 4B, 4C, eachoccupying one circuit cell, are laid out. Each ESD protection circuit4A, 4B, 4C occupies a rectangular circuit cell and the width 4W of threeESD protection circuits is larger than the width 5W of the outputcircuit 5. The layout pitch for the ESD protection circuits 4A, 4B, 4Cis equal to the layout pitch for the external drive terminals 3A, 3B,3C. By this relationship, the output protection circuits and theexternal drive terminals which are mutually coupled are associated inone-to-one correspondence in the X direction within the range of thewidth of 4W. On the other hand, because 4W>5W, positional relationshipbetween the output units 5A, 5B, 5C of the output circuits and theexternal drive terminals 3A, 3B, 3C which are mutually coupled is asfollows: distance between an output unit and its corresponding externaldrive terminal gradually increases, as the number of array columns frombase ends increases in the Y direction. FIG. 2 depicts the appearance ofthe array layout in which, when the right and left side ends of thesemiconductor substrate are viewed as array base ends, the distancebetween the output units 5A, 5B, 5C of the output circuits 5 and theexternal drive terminals 3A, 3B, 3C becomes father for array columnsnearer to the center. As is apparent from FIG. 2, the routing distancein the Y direction of wiring lines 8 coupling the output units 5A, 5B,5C of the output circuits 5 and the external drive terminals 3A, 3B, 3Cbecomes longer, the distance relative to each other becomes farther. Thewiring region 9 for this purpose is provided between the ESD protectioncircuits and the select circuits.

FIG. 3 representatively illustrates a positional relationship in whichESD protection circuits 4A, 4B, 4C and an output circuit 5 which areassociated with each other are relatively far from each other in the Ydirection. In FIG. 3, the ESD protection circuits 4A, 4B, 4C and theircorresponding external drive terminals 3A, 3B, 3C are coupled by wiringlines extending mostly in the X direction, which are, however, notshown, whereas the output circuit 5 which is associated with the ESDprotection circuits 4A, 4B, 4C is far in the Y direction and, therefore,wiring lines thereto are routed long in the Y direction. As noted above,by making the layout pitch in the Y direction for the ESD protectioncircuits 4A, 4B, 4C equal to the layout pitch in the Y direction for theexternal drive terminals 3A, 3B, 3C and by making 4W>5W, a circuitregion 6A is reserved. The wiring lines 8 are routed in the wiringregion between the ESD protection circuits 4A, 4B, 4C and the switchcircuits 53A, 53B, 53C. An ESD protection function is assured, as theexternal drive terminals 3A, 3B, 3C and the ESD protection circuits 4A,4B, 4C which are located near to each other are coupled to each other,without regard to their layout positions in the Y direction. If thehorizontal width of three ESD protection circuits 4A, 4B, 4C is reducedto 5W, the ESD protection circuits 4A, 4B, 4C are located near to theselect switches 53A, 53B, 53C, but some of the ESD protection circuits4A, 4B, 4C might become far from their corresponding external driveterminals 3A, 3B, 3C and there would be a risk that the ESD protectionfunction cannot be achieved sufficiently.

According to the above layout configuration, the external driveterminals 3A, 3B, 3C can be laid out at a narrower pitch by a staggeredarrangement of each set of these terminals in three columns in the Ydirection. In each output circuit 5 which is associated with each set ofthree external drive terminals 3A, 3B, 3C, by locating three outputunits 5A (50A, 51A, 52A, 53A), 5B (50B, 51B, 52B, 53B), and 5C (50C,51C, 52C, 53C) arranged in one column in the X direction, the totalwidth for three output units 5A can be compacted into the width (5W) ofone output circuit. It is thus possible to reduce the layout width of anoutput circuit 5 constrained by laying out the external drive terminals3A, 3B, 3C at a narrower pitch. Thereby, it is possible to sufficientlycomply with the requirement that the external drive terminals 3A, 3B, 3Cshould be arranged at a narrower pitch in the liquid crystal displaydriver 1. As is shown in a comparison example of FIG. 7, even ifexternal drive terminals are laid out in a staggered arrangement,however, in a configuration in which one set of a select switch, anoutput amplifier, a tone level selecting circuit, and a latch circuit isassociated with one external drive terminal and arranged in one column,it is inevitable that the width Wp of such set becomes considerablylarger than the widths 4W and 5W shown in FIG. 5 and the like.

In addition, because 4W>5W, it will be easy to reserve a surplus region6A for locating another circuit in a space provided between the arraysof output circuits 5 laid out in the Y direction. By effective use ofthis surplus region 6A for locating the processing circuit 6, it ispossible to improve the layout efficiency for locating circuits all overthe semiconductor substrate.

Since the ESD protection circuits 4A, 4B, 4C can be arranged near theexternal drive terminals 3A, 3B, 3C, it is possible to make assurancedoubly sure on protection against ESD. Because the wiring region 9 isthen provided between the array region of the ESD protection circuits4A, 4B, 4C and the select switches 53A, 53B, 53C, it will be easy toroute wiring lines for coupling the output circuits 5 to thecorresponding external drive terminals 3A, 3B, 3C.

As for external terminals not required to be laid out especially at anarrow pitch like the external interface terminals 7 that are used ashost interface or system interface, there is no need for theabove-described considerations with regard to the external driveterminals 3A, 3B, 3C

FIG. 4 illustrates a circuit configuration of output units of an outputcircuit. The circuit configuration shown here assumes driving the liquidcrystal display by alternating current drive such as line inversiondriving or dot inversion driving. This figure representativelyillustrates the configuration of output units 5A, 5B associated with apair of adjacent external drive terminals 3A, 3B.

The ESD protection circuits 4A, 4B are configured with a p-channel typediode-coupled MOS transistor Qdp in which a source electrode is coupledto a gate electrode between the external drive terminal 3A, 3B and apower supply terminal VDD and an n-channel type diode-coupled MOStransistor Qdn in which a source electrode is coupled to a gateelectrode between the external drive terminal 3A, 3B and a groundterminal GND.

The latch circuits 50A, 50B latch pixel data Ddi, Ddj for eachcorresponding pixel per horizontal scan timing and give the pixel datato the tone level selecting circuits 51A, 51B. The tone level selectingcircuits 51A, 51B are each supplied with a plurality of tone levelvoltages Vgrd for a number of tone levels such as 256 tone levels. Bydecoding the pixel data Ddi, Ddj, the tone level selecting circuits 51A,51B determine a tone level value and select and output one tone levelvoltage equivalent to the determined tone level value to thecorresponding output amplifiers 52A, 52B. The output amplifier 52Aamplifies and outputs a tone level voltage with positive polarity,whereas the output amplifier 52B amplifies and outputs a tone levelvoltage with negative polarity. Pois means an amplified tone levelvoltage output with positive polarity and Nega means an amplified tonelevel voltage output with negative polarity. The select switches 53A,53B complementarily select one of the outputs of the output amplifies52A, 52B in sync with horizontal scanning. Thereby, the select switch53A selects one of the positive/negative outputs and the select switch53A selects the other of the positive/negative outputs. By alternateswitching between the selected output states (positive/negative),alternating current drive by dot inversion driving can be accomplished.

Second Embodiment

FIG. 5 illustrates details on relative layouts of external driveterminals, ESD protection circuits, and output circuits, when each setof external drive terminals in two columns is laid out in a staggeredarrangement as a second embodiment of the present invention. In FIG. 5,six external drive terminals 3 mA, 3 mB, six ESD protection circuits 4mA, 4 mB, and three output circuits 5 m are shown by way of example.

One output circuit 5 m has two output units 5 mA, 5 mB. Here, theexternal drive terminals 3 mA, 3 mB are terminals for driving sourceelectrodes of the active matrix type liquid crystal display. The outputunits 5 mA, 5 mB, respectively, include latch circuits 50 mA, 50 mB thatlatch display data supplied from the processing circuit 6, tone levelselecting circuits 51 mA, 51 mB that decode the display data latched bythe latch circuits 50 mA, 50 mB and select a tone level voltage signal,output amplifiers 52 mA, 52 mB that amplify tone level voltage signalswhich have been output from the tone level selecting circuits 51 mA, 51mB, and select switches 53 mA, 53 mB that select one of the outputs withopposite polarities of two output amplifiers and output it to thecorresponding external drive terminals 3 mA, 3 mB. The output unit 5 mAincludes a latch circuit 50 mA, a tone level selecting circuit 51 mA, anoutput amplifier 52 mA, and a select switch 53 mA. The output unit 5 mBincludes a latch circuit 50 mB, a tone level selecting circuit 51 mB, anoutput amplifier 52 mB, and a select switch 53 mB. Here, the outputunits 5 mA, 5 mB are not arranged on a per-unit basis; instead,component circuits of each output unit are arranged together on aper-function basis. For example, the select switches 53 m, 53 mB arearranged in line in the Y direction, whereas the output amplifiers 52mA, 52 mB, the tone level selecting circuits 51 mA, 51 mB and the latchcircuits 50 mA, 50 mB are arranged in line in the X direction in thementioned order.

A large number of output circuits 5 m, each occupying one circuit cell,are laid out. One output circuit occupies a rectangular circuit cellhaving a width of 5 mW.

Also, a large number of ESD protection circuits 4 mA, 4 mB, eachoccupying one circuit cell, are laid out. Each ESD protection circuit 4mA, 4 mB occupies a rectangular circuit cell and the width 4 mW of twoESD protection circuits is larger than the width 5 mW of the outputcircuit 5 m. The layout pitch for the ESD protection circuits 4 mA, 4 mBis equal to the layout pitch for the external drive terminals 3 mA, 3mB. By this relationship, the output protection circuits and theexternal drive terminals which are mutually coupled are associated inone-to-one correspondence in the X direction within the range of thewidth of 4W. On the other hand, because 4 mW>5 mW, positionalrelationship between the output units 5 mA, 5 mB of the output circuitsand the external drive terminals 3 mA, 3 mB which are mutually coupledis as follows: distance between an output unit and its correspondingexternal drive terminal gradually increases, as the number of arraycolumns from base ends increases in the Y direction. The routingdistance in the Y direction of wiring lines 8 coupling the output units5 mA, 5 mB of the output circuits 5 m and the external drive terminals 3mA, 3 mB becomes longer, the distance relative to each other becomesfarther. The wiring region 9 m for this purpose is provided between theESD protection circuits and the select circuits.

When making a comparison between the first embodiment in which each setof external drive terminals in three columns is laid out in a staggeredarrangement and the second embodiment in which each set of externaldrive terminals in two columns is laid out in a staggered arrangement,if there is a limit of the length in the X direction of the outputcircuits 5, 5 m and the output circuits 5, 5 m extend in the X directionup to the limit, 5 mW is shorter than 5W. If a pitch for the externaldrive terminals can be set so that a minimum necessary interval (forexample, 11 μm) can be provided between adjacent terminals in each set,the width dimension of 4W remains unchanged even if the number ofcolumns in which the terminals are laid out in a staggered arrangementin the Y direction increases. However, the layout pitch for the entirearray of external drive terminals becomes smaller, as the number ofcolumns in which the terminals are laid out in a staggered arrangementin the Y direction increases. Therefore, it will be expedient that thenumber of columns in which the terminals are laid out in a staggeredarrangement should be increased commensurate with a narrow pitchdesigned for input terminals or input wiring lines of a driven device tobe coupled to the external drive terminals. The smaller the number ofcolumns in which the terminals are laid out in a staggered arrangement,a lager empty space region 6A can be reserved.

In other respects, the second embodiment can achieve a similar positiveeffect as is the case for the first embodiment.

Third Embodiment

FIG. 6 illustrates a mobile phone as a third embodiment of the presentinvention. The mobile phone (MBLPHN) 100, which is an example of amobile information terminal, includes an input unit 102 that acceptsuser input such as key in operation, a data processing unit 103 thatperforms data processing according to an input signal from the inputunit 102, and a display panel (LCDPNL) 104 as a display unit for displayunder control of the data processing unit 103 in the mobile phone'scasing 101. The input unit 102 is not limited to a key in structure anda touch panel or the like may be used as the input unit. The dataprocessing unit 103 involves, but not limited to, a baseband processingunit for mobile communication and application processing units fordisplay control, authentication for communication, etc. The displaypanel 104 includes an active matrix type liquid crystal display (DISP)111 formed over a glass substrate 110, source electrode lines 112 madeof, for example, an ITO film (a transparent conductive film of indiumoxide with an additive of oxide) or the like, lead out from the activematrix type liquid crystal display 11, and formed over the glasssubstrate 110, and a liquid crystal display driver (LCDDRV) 1, as asemiconductor integrated circuit, coupled to the source electrode lines112 and mounted over the glass substrate 110. The liquid crystal displaydriver 1 has the configuration described in the first embodiment or thesecond embodiment. Reference numeral 113 denotes collectively interfacecables for coupling the liquid crystal display driver 1 to theapplication processing units.

Because, as is evident from the foregoing description, the liquidcrystal display driver 1 sufficiently complies with the requirement thatthe external drive terminals 3A, 3B, 3C (3 mA, 3 mB) should be arrangedat a narrower pitch, the inventive feature in terms of narrower pitchlayout of the external drive terminals 3A, 3B, 3C (3 mA, 3 mB) of theliquid crystal display driver 1 for driving pixels of the active matrixtype liquid crystal display 111 can contribute to the realization of asmaller display panel and, moreover, a smaller mobile phone in order tomeet size reduction and enhanced definition of the active matrix typeliquid crystal display 111.

While the invention made by the present inventors has been describedspecifically based on its embodiments hereinbefore, it will beappreciated that the present invention is not limited to the describedembodiments and various modifications may be made thereto withoutdeparting from the scope of the invention.

For example, mapping three output units of an output circuit 5 toexternal drive terminals to which they are coupled respectively is notlimited to mapping them to the terminals 3A, 3B, 3C in a set laid out inthree columns in every case. The output units may be mapped to theterminals in a set laid out in a triangle arrangement in two columns outof three columns.

The arrangement of select switches 53A, 53B, 53C is not limited toarranging them in line in the Y direction; they may be arranged in linein the X direction.

Mobile information terminal is not limited to a mobile phone; it may bea terminal for communication via a wireless LAN instead of mobilecommunication or a terminal for stand-alone use without anycommunication function.

The number of columns in which each set of external drive terminals islaid out in a staggered arrangement is not limited to two or threecolumns; a number of columns more than three can be adopted, asappropriate.

1-13. (canceled)
 14. A semiconductor device including a liquid crystaldisplay (LCD) driver, comprising: a semiconductor substrate of arectangular shape which has a pair of long sides and a pair of shortsides in a plan view; a plurality of output circuits disposed along afirst direction parallel to the pair of the long sides on thesemiconductor substrate; and a plurality of external drive terminalsdisposed over and overlapping each of the plurality of output circuits,wherein a distance between one of the pair of long sides and one of theplurality of external drive terminals is greater than that between saidone of the pair of long sides and another one of the plurality ofexternal drive terminals.
 15. The semiconductor device according toclaim 14, wherein a distance between one of the pair of short sides andone of the plurality of external drive terminals is greater than thatbetween said one of the pair of short sides and another one of theplurality of external drive terminals.
 16. The semiconductor deviceaccording to claim 14, wherein each of the plurality of output circuitsincludes a plurality of output amplifiers which are disposed along asecond direction parallel to the pair of the short sides, and each ofthe plurality of external drive terminals overlaps with each of theplurality of plurality of output amplifiers in the plan view.
 17. Thesemiconductor device according to claim 14, wherein the plurality ofexternal drive terminals are laid out in a staggered arrangement in theplan view.
 18. The semiconductor device according to claim 14, whereinthe plurality of external drive terminals are configured to couple withsource lines of an LCD.
 19. The semiconductor device according to claim14, wherein each of the plurality of external drive terminals is asolder bump.
 20. The semiconductor device according to claim 15, whereineach of the plurality of output amplifiers is configured to amplify tonelevel voltage signals.
 21. The semiconductor device according to claim14, wherein each of the plurality of output circuits includes: aplurality of latch circuits configured to latch display data; aplurality of tone level selecting circuits configured to decode thedisplay data latched by the latch circuits and select a tone levelvoltage signal; a plurality of output amplifiers configured to amplifythe tone level voltage signals from the tone level selecting circuits;and a plurality of select switches configured to select one of theoutputs from the plurality of output amplifiers.
 22. The semiconductordevice according to claim 14, further comprising: a plurality of ESDprotection circuits, wherein each of the plurality of ESD protectioncircuits is coupled with each of the plurality of external driveterminals.
 23. The liquid crystal display driver according to claim 14,further comprising: an ESD circuit region including a plurality of ESDprotection circuits arranged along the second direction, wherein theoutput circuit region is disposed over and overlaps with the ESD circuitregion.
 24. A liquid crystal display driver comprising: an outputcircuit region including a plurality of output circuits each arrangedalong a first direction of the output circuit region; and a plurality ofexternal drive terminals disposed over and overlapping with the outputcircuit region, wherein the external drive terminals are arranged in afirst interval along the first direction, and are shifted in a seconddirection in a second interval.
 25. The semiconductor device accordingto claim 24, wherein each of the plurality of output circuits includes:a plurality of latch circuits configured to latch display data; aplurality of tone level selecting circuits configured to decode thedisplay data latched by the latch circuits and select a tone levelvoltage signal; a plurality of output amplifiers configured to amplifythe tone level voltage signals from the tone level selecting circuits;and a plurality of select switches configured to select one of theoutputs from the plurality of output amplifiers.